The present invention relates to a silver halide photographic photosensitive material and a method for producing it. More particularly, it relates to method for producing a silver halide photographic film photosensitive material having polyethylene terephthalate support and excellent in dimensional stability.
Ordinarily, fiber ester (hereinafter referred to as "triacetate"), polyethylene terephthalate (hereinafter referred to as "polyester") or the like is used as a support in silver halide film photosensitive materials. However, with reference to expansion and shrinkage of film photosensitive material, when a polyester support of 100 .mu.m thick is used, rate of dimensional change per change of 1.degree. C. in temperature is 1 .times.10.sup.-3 % and rate of change per change of 1% in relative humidity is 1.5.times.10.sup.-3 %. Furthermore, in the case of triacetate support, the rate of change is 3.times.10.sup.-3 % per change of 1.degree. C. in temperature and the rate of change per change of 1% in relative humidity is 4.5.times.10.sup.-3 %, namely, it shows changes of 3 times that of the polyester support. This expansion and shrinkage (dimensional change) cause problems in the field where dimensional accuracy is required For example, in the case of film for plate making used in the field of printing, four color printing as in color printing is carried out and unless the four colors overlap perfectly with each other, attractive prints cannot be obtained. Furthermore, increase in the size of print and complication of prints such as the complicated expression of letters require improvement in accuracy of dimensional stability of film for plate making. In this field of printing, film photosensitive materials for plate making in which polyester is used as support is also mainly used, but those which are satisfactory in dimensional stability have not yet been obtained and the severe control of the environment in use (temperature, humidity) has been conducted.
As techniques for improvement of dimensional stability, incorporation of polymer latex into silver halide emulsion is disclosed, for example, in Japanese Patent Kokoku (Post Exam. Publn.) Nos. 39-4272, 45-5331 and 55-47371 and Japanese Patent Kokai (Laid-Open) Nos. 61-251844 and 63-244031. However, there are problems in the production of photosensitive materials and in the quality such as adverse effects on photographic performances, loss loss of clarity in development, the increase of viscosity of the coating solution, the deterioration of double-coatability and repelling in coating.
Many hardeners for hardening gelatin-containing layers are known and among them, active halogen type hardeners are well known as excellent hardeners having high film hardening properties. For example, various active halo9en type hardeners and methods for use thereof are disclosed in Japanese Patent Kokoku (Post Exam. Publn.) Nos. 39-16928, 43-2602, 47-6151, 47-33380 and 48-13709 and Japanese Patent Kokai (Laid-Open) Nos. 48-3527, 48-31937, 51-9434, 51-78788, 52-60612, 52-127229, 54-15958 and 56-27135.
These hardeners are added to the coating solution for the photographic layer before coating on the support and the coating solution is coated and dried and then wound up. The photographic coat immediately after coating and drying contains the hardener in the unreacted state with the binder and the film strength of the coat is not yet high enough to stand photographic treatment. The reaction of such unreacted hardener with the binder still proceeds after coating and drying of the photographic layer and so when the photographic material is left to stand for a long time before shipping, a film strength high enough to stand cannot be controlled by such a method and especially dimensional stability which requires accuracy cannot be controlled at all. Therefore, heating of the coat is carried out to accelerate the reaction of hardener, but for further acceleration of the reaction, the water content in the gelatin layer must be increased and, in general, the heating is carried out while keeping the water content of 22-25% by weight based on the weight of gelatin.
In the case of laminated paper (RC base) or triacetate film base, the amount of water contained in the base is large and this assists the hardening reaction during heating and the limiting of water content is not needed. These bases are essentially inferior in dimensional stability and are not used for a purpose which requires accuracy.
As a result of intensive research conducted by the inventors on dimensional stability, it has been found that the water content in gelatin layer containing an active halogen type hardener has a great effect on the dimensional stability. That is, it is proposed to reduce the water content and to carry out heating treatment under severer conditions than conventional treatment (for example, by prolonging heating time, raising the temperature, increasing the amount of hardener, etc.).